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1.
以光镜和电镜观察了日本蟳精子的形态结构,对雄体贮精囊和雌体纳精囊中的精子结构进行了比较,并研究了pH,盐度对日本蟳精子存活率的影响规律,结果表明:日本蟳精子为非鞭毛型,主要由顶体、核杯、膜复合体和辐射臂等组成,其中顶体呈球形或近球形,可分成头帽、顶体管和顶体囊三部分。核杯包裹整个顶体外围,染色质呈细丝状或颗粒状。辐射臂向精子四周发出,内含核质,没有运动能力。雄体贮精囊中的精子包裹在椭球形精荚中,而雌体纳精囊中的精子呈弥散状,精子顶体管中有囊泡状结构、中心体位置前移、胞质透明区扩大,而且有些精子已崩解。精巢表面pH为6.5±0.2,精液pH为7.0±0.2,精子密度平均为(3.47×109±0.42×109)个/cm3。精子的适宜pH为7~9,最适pH为8;适宜盐度为20~30,最适盐度为25。  相似文献   

2.
为揭示赤点石斑鱼精子的超微结构及环境因子对其精子活力的影响,利用扫描电镜和透射电镜观察赤点石斑鱼精子的超微结构,设置不同梯度的温度、盐度、pH值及不同浓度的NaCl、KCl、CaCl2、MgCl2、EDTANa2溶液,探究这些因子对赤点石斑鱼精子活力的影响。结果表明:赤点石斑鱼成熟精子的结构特点是细胞核圆形或卵圆形,核内染色质致密,没有核泡(核空隙)。精子尾部细长,横切面为典型的"9+2"微管结构。温度、盐度、pH值等环境因子对精子活力的影响表明,精子活力的适宜温度范围为23~31℃,27.5℃时精子寿命最长为37min;适宜的盐度范围为15~35,盐度15时精子寿命最长为50min;适宜的pH范围为7~9,pH为9时精子的运动时间最长为33min。赤点石斑鱼精子在EDTANa2溶液中呈抑制状态,在400~700 mmol/L的NaCl溶液、400~600mmol/L的KCl溶液和500 mmol/L的CaCl2溶液中精子均具有较好的活动能力。在MgCl2溶液中赤点石斑鱼精子的活动能力不佳。赤点石斑鱼精子的最适温度范围与繁殖季节的最适水温范围符合,适宜盐度范围较广,对pH值的变化适应性较强。赤点石斑鱼精子在NaCl、KCl、CaCl2溶液中活力较佳,在MgCl2溶液和EDTANa2溶液中呈抑制状态。  相似文献   

3.
于1988—1989年,对中国对虾的成熟精子用透射电镜和扫描电镜进行了超微结构的研究,结果表明,中国对虾精子系单一棘突类型,主要由前端棘突、中间帽状体和后主体部构成;精子没有尾部,缺少线粒体,不主动运动。比较了来自雄虾体内和雌虾纳精囊内精子的相异之处,发现:(1)雄虾体内精子较粗短,棘突有螺旋结构,而雌虾纳精囊中的则相反;(2)雄虾体内精子核后细胞质带结构更完整,而雌虾纳精囊中精子核后细胞质带囊泡发达并常与质膜融合发生胞吐现象;(3)雄虾体内精子核膜比雌虾纳精囊精子核膜完整;(4)雌虾纳精囊精子的环状片层结构更发达。  相似文献   

4.
中华绒螯蟹精子的研究——Ⅰ.精子的形态及超微结构   总被引:11,自引:0,他引:11  
中华绒螯蟹的精子属无鞭毛精子。扫描电镜观察表明,这类精子呈不规则扁球形,前端有一光滑的圆面,圆面四周是凹陷的沟环,沟环后的精子表面凹凸不平,并伸出约20条辐射臂。透射电镜揭示了这类精子是由球形的顶体、杯状的核杯及辐射臂所组成,其中顶体形态较为复杂,包含多种亚显微结构。细胞化学反应证明了核杯为Feulgen阳性,顶体为PAS阳性。  相似文献   

5.
大黄鱼精子生理特性及其冷冻保存   总被引:14,自引:0,他引:14  
研究了大黄鱼精子的生理特性及其冷冻保存技术。实验结果表明,大黄鱼精液pH值为6.72—7.25。精子平均密度为14.45×109·ml-1。精子离体后在精液中3.5h(25℃)仍有80.5%可以存活。在精子激活液中,不同的盐度和酸碱度对精子的活力、存活时间和运动状况影响很大。精子适宜的盐度为20—35,pH值为6.60—8.50。在海水中精子的直线快速运动仅持续3min。使用筛选出的精液稀释液和抗冻剂组成精子冷冻保存液。采用快速冷冻保存方法在液氮中保存精子。经保存1a,采用室温(21—23.5℃)自然解冻冻精,精子活力可达到89.5%±4.2%。利用冻精进行大黄鱼的人工授精试验,受精率达82.7%±5.5%,孵化率达85.7%±5.8%,与鲜精对照组相近。  相似文献   

6.
中华绒螯蟹精子的研究 Ⅱ.精子发生   总被引:21,自引:2,他引:21       下载免费PDF全文
对中华绒螯蟹(Eriocheir sinensis)精子发生全过程的电镜观察表明:精原细胞较大,卵圆形,线粒体和内质网小泡集中在细胞一端,形成“线粒体区”;初级精母细胞多边形,拟染色体包围中心粒形成中心粒附属物;早期精细胞中内质网小泡分泌产生原顶体颗粒,中期聚合成大的原顶体囊;细胞核逐渐变化而呈杯状,并包裹顶体囊,形成精子;随着精子的成熟,顶体进一步分化;成熟时,核杯向外伸出辐射臂。  相似文献   

7.
为探讨星康吉鳗(Conger myriaster)精子的超微结构和形态,应用扫描电镜和透射电镜对星康吉鳗精子结构进行观察。结果表明,精子由头部、中段和鞭毛3部分组成,有其独特的结构,总长度为35.75± 1.15µm。精子头部为新月形,主要由细胞核构成,细胞核内有核泡,无顶体结构。精子头部的质膜内包含单一的线粒体。精子头部长为3.33±0.16 um,头宽为1.12±0.13 um。在精子头部的凸面上,有4条从中段到头端的条纹。精子中段伸出一支根,支根位于精子的中段末端。精子中段长度为0.55±0.05 um,支根长度为1.38±0.08 um、直径为90.48±6.06 nm。精子尾部鞭毛细长,鞭毛横切面呈圆形,无侧鳍,鞭毛的轴丝结构为“9+0”型;一些鞭毛的末端呈现卷曲状,发育机制尚不明确。精子鞭毛长为31.16±1.51µm,鞭毛直径为0.17±0.01µm。通过比较分析发现精子的这些形态学特征不仅表现在星康吉鳗精子,还表现在鳗鲡目其他属的精子;表明是鳗鲡目精子的共同特征。本研究揭示了星康吉鳗精子的形态结构,为突破星康吉鳗人工繁殖技术提供了理论参考。  相似文献   

8.
中国对虾(Penaeus chinensis)精子ATP酶活力与生殖关系的探讨   总被引:3,自引:0,他引:3  
首次报道了中国对虾精子存在有Na,K-ATP酶及Mg-ATP酶活力,并对 其生物功能进行了探讨。对来自不同季节的雌虾纳精囊中精子的两种ATP酶活力 进行了测定。酶分析的结果为春虾精子的 Na,K-ATP酶活力为 1.145±0.229μmol Pi/mg· h,秋虾则为 1. 058±0. 431μmol Pi/mg· h;春虾精子的 Mg-ATP酶活力为 1. 647±0. 691μmol Pi/mm· h,秋虾则为 1. 584±0. 315μmol Pi/mg· h。因此在表观 上,春虾精子的两种ATP酶活力均略高于秋虾,但差异不够显著。  相似文献   

9.
研究了盐度、pH对点带石斑鱼(Epinephelus malabaricus)精子活力的影响;同时对超低温冷冻前后点带石斑鱼精子的超微结构进行了比较观察。研究结果表明:(1)该鱼精子活力的适宜盐度范围为15-35,盐度为15时,精子寿命最长为26 min;最适pH值范围为6.5-8.0,当pH值为7.5时,精子的寿命最长为4 min;(2)超低温冷冻保存前,正常的点带石斑鱼精子由头部、中段和尾部3部分组成,精子头部呈球圆形或近圆形,直径约1.8 m;中段不明显,可见线粒体;鞭毛细长,约15 m,尾部主要结构是轴丝,为典型"9+2"微管结构;(3)超低温冷冻保存后,点带石斑鱼精子的形态结构损伤明显,主要表现为质膜褶皱、破裂,细胞质外漏,线粒体膨胀破损,脱落和鞭毛断裂等特征。  相似文献   

10.
环境因子变化对泥蚶精子活力的影响   总被引:5,自引:0,他引:5  
研究了pH、盐度及温度对泥蚶(Tegillarca granosa)精子的激活及运动情况的影响。结果表明,泥蚶精子激活及运动的较适宜环境条件为:pH 7~9.5、盐度15~35、水温25~35℃;最适环境条件为:pH 8.5、盐度25、水温30℃。分析表明,泥蚶精子激活与运动的适宜环境条件与泥蚶的生态栖息环境、繁殖条件相统一。  相似文献   

11.
The food sources of aquacultured Apostichopus japonicus and the trophic levels of organisms in a sea cucumber(A. japonicus) and prawn(Penaeus japonica) polyculture system in a saltwater pond in Zhuanghe, Liaoning Province were examined using carbon and nitrogen stable isotopes. Across organisms, δ13C ranged from(–25.47±0.20)‰ to(–16.48±0.17)‰(mean±SD), and δ15N ranged from(4.23±0.49)‰ to(12.44±0.09)‰. The δ13C and δ15N contents of A. japonicus, P. japonica and Fenneropenaeus chinensis were comparatively higher than those of other organisms. Values of δ13C and δ15N revealed that P. japonica, Hemigrapsus sanguineus and Neomysis japonica comprised the largest component of the diet of A. japonicus. The mean trophic level of the organisms in this saltwater pond polyculture system was(2.75±0.08). P. japonica, A. japonicus, F. chinensis,Synechogobius hasta and Neomysis japonica were in the 3rd trophic level(2–3); jellyfish, H. sanguineus and zooplankton were in the 2nd trophic level(1–2); and Enteromorpha prolifera, benthic microalgae, periphyton and suspended matter primarily consisting of phytoplankton, bacteria and humus were in the primary trophic level(0–1).  相似文献   

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14.
The temporal dynamics of two seagrass species, Zostera marina and Z. japonica, were monitored monthly in Dadae Bay, Geoje Island, on the southern coast of Korea. Plant morphological characteristics, shoot density, biomass, leaf production, reproductive effort, and environmental characteristics were monitored from July 2001 to July 2002. Zostera japonica occurred in the intertidal zone and Z. marina occurred in the subtidal zone from 0.5 to 2.5 m below the mean low water level. Shoots and rhizomes were significantly larger in Z. marina than in Z. japonica, whereas the shoot density was greater in Z. japonica than in Z. marina. Despite differences in morphology and shoot density, biomass did not differ significantly between the species. Reproduction occurred from April to June in Z. marina and from May to July in Z. japonica. The proportion of reproductive shoots was approximately three times higher in Z. marina than in Z. japonica. Seasonal variation in the biomass of Z. japonica was caused by changes in both shoot size and density, whereas that of Z. marina was mainly caused by changes in shoot length. Leaf production in Z. marina and Z. japonica showed clear seasonal variation, and leaf production in Z. marina (2.6 ± 0.2 g DW·m−2·day−1) was higher than that in Z. japonica (1.7 ± 0.2 g DW·m−2·day−1). The mean plastochrone interval was not significantly different between the two species, whereas the leaf lifetime of Z. marina was longer (69 ± 7.8 days) than that of Z. japonica (59 ± 8.3 days). Our results indicated that seasonal leaf growth patterns in Z. japonica are correlated with irradiance and temperature, whereas those in Z. marina respond most to irradiance. Seasonal changes in irradiance appeared to control the temporal variation in above‐ground biomass in both species.  相似文献   

15.
中国对虾受精生物学的研究   总被引:13,自引:1,他引:13  
于1988-1991年在青岛对中国对虾进行受精能力和受精生物学的研究。对虾采用加温和不加温培育,然后用人工授精法--水域法和滴管法授精研究精卵受精能力;应用扫描和透射电以及石蜡切片技术,精卵的形态结构和受精过程的变化。结果表明,水域法授精,精子入水后3h仍具有受精能力;卵子入水后1min之内受精率最高只达62.7%。而滴客法授精,受精率最高可达到98%。平均值也在60-80%之间。保持在低温的亲虾  相似文献   

16.
The genome size(C-value) of an organism is referring to the DNA content of its non-replicated haploid chromosome complement,generally deduced from measuring somatic diploid nuclei.We presented genome size(C-value) data obtained by flow cytometry for four commercially important crabs(Portunus trituberculatus,Charybdis japonica,Scylla paramamosain,and Eriocheir sinensis) common in the coast of China.Gallus domesticus(2C=2.5 pg) was used as the internal standard.The results showed that the C-value for P.trituberculatus,C.japonica,S.paramamosain,and E.sinensis were(2.31±0.01) pg,(2.33±0.03) pg,(1.64±0.02) pg,and(2.29±0.03) pg,respectively.The C-value of P.trituberculatus,C.japonica and S.paramamosain were reported for the first time.The data represented by the four species indicated that they had lower DNA contents than average DNA values in crustaceans((4.99±0.48) pg),and three of the four values were very similar if not identical.The results provide useful data for future studies in the fields of biodiversity,species conservation,and phylogeny of these commercial crabs.They will also be helpful in instructing the hybridization breeding program and estimating the cost of the whole genome sequencing project.  相似文献   

17.
根据2014年8月和10月、2015年2月和5月使用单船底拖网进行的4个航次调查数据,对山东半岛近岸海区的莱州湾及渤海南部、山东半岛北部和山东半岛南部等3个海域蟹类种类组成、时空分布、优势种、群落结构稳定性等群落结构特征进行了研究。结果显示,4次调查共捕获蟹类20种,隶属于10科17属,其中日本蟳(Charybdis japonica)和三疣梭子蟹(Portunus trituberculatus)是主要经济种类,其余均为小型饵料型蟹类;海区内主要的优势种为双斑蟳(Charybdis bimaculata)、日本蟳(Charybdis japonica)和三疣梭子蟹(Portunus trituberculatus),3个海域优势种季节更替均十分明显;莱州湾及渤海南部和山东半岛南部2个海域生物量季节变化明显,春季较低,在夏季达到峰值,夏季到冬季呈降低趋势,山东半岛北部海域生物量季节变化不明显。3个海域蟹类群落物种多样性指数(H')、丰富度指数(D)及均匀度指数(J')均处于较低水平,并有一定的季节变化;水深、水温和盐度是影响蟹类群落结构的重要因子,渤莱沿岸流、黄海暖流和黄海冷水团通过影响海域内水温与盐度影响蟹类群落结构。研究表明山东半岛近岸海区蟹类以小型饵料型蟹类为主,蟹类多样性水平较低,优势种更替明显,群落季节更替指数较高,季节间迁移频繁,蟹类群落不稳定。  相似文献   

18.
利用离子交换层析和凝胶过滤层析等方法,从日本(Charybdis japonica)血淋巴中分离纯化出了酚氧化酶,并以L-二羟苯丙氨酸(L-DOPA)作为特异性底物对其生化性质和酶性质进行了研究。结果表明,酚氧化酶和酚氧化酶原的分子质量分别为64.5 ku和69.5 ku。以L-DOPA为底物对酚氧化酶纯品进行研究发现,其最适pH值为6.0、最适温度为40℃。对底物L-DOPA和儿茶酚的米氏常数Km值分别为3.41和7.97 mmol/L。该酶对亚硫酸钠、苯硫脲极为敏感,对硫脲、苯甲酸非常敏感,表明该酶很可能是一种儿茶酚酶型的酶。此外,EDTA,DETC,Zn2 ,Mg2 和Cu2 均能显著抑制该酶活性,且10 mmol/L Cu2 能有效地回复该酶被DETC所抑制的酶活性,表明该酶确为一种Cu-金属酶。  相似文献   

19.
The intertidal seagrass Zostera japonica, which is distributed in the intertidal and shallow subtidal zones, is exposed to nutrients from over-enriched land-based discharge and storm water runoff before they can be washed out to sea. Despite its ecological importance, only a few studies have examined the ecology and physiology of Z. japonica in northeast Asia. In this study, we investigated the productivity and tissue nutrient contents of above- and below-ground tissues to evaluate the potential role of Z. japonica in carbon capture and as a nutrient sink. The average total, above-, and below-ground productivity per shoot was 0.56, 0.34, and 0.21 mg DW shoot-1 day-1, respectively. Annual leaf production was 1.5 times higher than annual below-ground production. Estimated annual whole-plant carbon, nitrogen, and phosphorus incorporation based on shoot production and tissue nutrient contents was 312.8 g C m-2 y-1, 25.7 g N m-2 y-1, and 1.6 g P m-2 y-1, respectively. These values were equivalent to 7.8 × 103 kg C y-1, 6.4 × 102 kg N y-1, and 40 kg P y-1 for all Z. japonica beds in Geoje Bay. This suggests that Z. japonica meadows can incorporate a considerable amount of carbon, nitrogen, and phosphorus in the intertidal zone. High N:P ratios of above- and below-ground tissues suggest that Z. japonica growth is probably limited by phosphorus availability in the study area.  相似文献   

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